Generally, an existing centralized power supply module for a server cabinet, or a conventional busbar assembly for a power distribution unit includes a plurality of copper busbars. Each copper busbar is in the form of a broad plate that has a large area to allow passage of high currents and effective dissipation of heat.
In conventional busbar assemblies, two copper busbars are interconnected in various fashions in order to vary directions of current flows. However, processing of the copper busbars includes bending operations to shape the copper busbars, and requires relatively large area copper plates, thus increasing costs due to material redundancy. Further, owing to the increasing requirement of high power density, the existing server cabinet may not have sufficient interior space for accommodation of busbars, and difficulty may increase in assembly and maintenance. Because server cabinets with compact layouts become a significant demand, each copper busbar has to be tailored after being bent in order to be accommodated in the limited space of the server cabinet and to be inter-connectable with another busbar. Manufacturing costs are increased due to the need of tailoring subsequent to bending (the bending operations) and formation of substantial scrap resulting from tailoring.
Referring to FIGS. 1 and 2, the conventional busbar assembly 9 includes two busbar subassemblies 91, 92. Because the busbar subassemblies 91, 92 are structurally identical, only one of the busbar subassemblies 91, 92 is described hereinafter. The busbar subassembly 91 includes a first copper busbar 911 and a second copper busbar 912 attached to the first copper busbar 911. The first copper busbar 911 is a horizontally-arranged flat plate, formed in rectangular shape. The second copper busbar 912 has a horizontally-arranged flat plate portion 913 attached to a top surface of the first copper busbar 911, and a vertically-arranged flat plate portion 914 bending downwardly from the horizontally-arranged plate portion 913. During manufacture of the second copper busbar 912, a rectangular copperplate 90 is first cut to form a semi-finished product 901 and a certain amount of scrap waste 902. Subsequently, the semi-finished product 901 is subjected to a bending process, wherein bending the semi-finished busbar 901 along a predetermined bending line 903 produces a plate portion 904 that is bent perpendicularly from a plate portion 905, thereby forming the second copper busbar 912. The bending line 903 is oblique to a lengthwise direction of either one of the plate portions 904, 905 and formed at a position where the plate portions 904, 905 meet each other. Manufacturing the second copper busbar 912 as such results in an increased cost because of the additionally needed cutting process, which produces a large amount of scrap.